The present invention relates to texture discrimination which is best adapted to discriminating the whole area, in which two kinds of textures are present in a mixed manner, into the areas for each of the kind of textures, and particularly which is best adapted to automatically discriminating the characters from a headline area with a background texture of a printed matter such as a newspaper, a magazine or the like.
Accompanying the widespread use of personal computers or word processors and the reduction in the cost of the recording media in recent years, documents in the form of data base and electronic filing of printed matter have been occupying important positions in office automation. In particular, it has been desired to construct an automatic document register/retrieval system capable of storing data contained in the printed documents such as newspaper, magazines and official documents, and capable of retrieving required information only therefrom. At the time of registering, this system automatically divides, first, the document into a headline area, a text area and a photo area through image processing. In the former two areas, the characters are encoded by character recognition and, then, character code sequences and photo image data are registered. With the file registered in such a form, the cost for storage and transfer is cheaper and the retrieval of contents is easier than when the whole document is stored as an image. In an attempt to develop such systems, therefore, study and research have been as described, for example, in the Trans. of IEICE (the Institute of Electronics, Information and Communication Engineers of Japan) "A Method of Document-Image Segmentation based on Projection Profiles, Stroke Densities and Circumscribed Rectangles", Vol. J69-D, No. 8, August, 1986.